Evaluation of the influence of kyphosis and scoliosis on intervertebral disc extrusion in French bulldogs

Although thoracic vertebral malformations with kyphosis and scoliosis are often considered incidental findings on diagnostic imaging studies of screw-tailed brachycephalic breeds, they have been suggested to interfere with spinal biomechanics and intervertebral disc degeneration. It is however unknown if an abnormal spinal curvature also predisposes dogs to develop clinically relevant intervertebral disc herniations. The aim of this study was to evaluate if the occurrence of thoracic vertebral malformations, kyphosis or scoliosis would be associated with a higher prevalence of cervical or thoracolumbar intervertebral disc extrusion in French bulldogs

Equine cervical intervertebral disc degeneration is associated with location and MRI features

Morphology of the equine cervical intervertebral disc is different from that in humans and small companion animals and published imaging data are scarcely available. The objectives of this exploratory, methods comparison study were (a) to describe MRI features of macroscopically nondegenerated and degenerated intervertebral discs (b) to test associations between spinal location and macroscopic degeneration or MRI-detected annular protrusion and between MRI-detected annular protrusion and macroscopic degeneration, and (c) to define MRI sequences for characterizing equine cervical intervertebral disc degeneration. Ex vivo MRI of intervertebral discs was performed in 11 horses with clinical signs related to the cervical region prior to macroscopic assessment. Mixed-effect logistic regression modeling included spinal location, MRI-detected annular protrusion, and presence of macroscopic degeneration with "horse" as random effect. Odds ratio and 95% confidence interval were determined. Reduced signal intensity in proton density turbo SE represented intervertebral disc degeneration. Signal voids due to presence of gas and/or hemorrhage were seen in gradient echo sequences. Presence of macroscopic intervertebral disc degeneration was significantly associated with spinal location with odds being higher in the caudal (C5 to T1) versus cranial (C2 to C5) part of the cervical vertebral column. Intervertebral discs with MRI-detected annular protrusion grades 2-4 did have higher odds than with grade 1 to have macroscopic degeneration. It was concluded that MRI findings corresponded well with gross macroscopic data. Magnetic resonance imaging of the equine cervical intervertebral disc seems to be a promising technique, but its potential clinical value for live horses needs to be explored further in a larger and more diverse population of horses

Spinal Nerve Root Swelling Mimicking Intervertebral Disc Herniation in Magnetic Resonance Imaging -A Case Report-

A herniated intervertebral disc is the most common type of soft tissue mass lesion within the lumbar spinal canal. Magnetic resonance imaging (MRI) is a useful tool for the assessment of patients with lower back pain and radiating pain, especially intervertebral disc herniation. MRI findings of intervertebral disc herniation are typical. However, from time to time, despite an apparently classic history and typical MRI findings suggestive of disc herniation, surgical exploration fails to reveal any lesion of an intervertebral disc. Our patient underwent lumbar disc surgery with the preoperative diagnosis of lumbar disc herniation; however, nothing could be found during the surgical procedure, except a swollen nerve root

Clarifying the nomenclature of intervertebral disc degeneration and displacement: from bench to bedside

As a significant determinant of low back pain, intervertebral disc degeneration (IDD) has attracted more and more attention of both investigators and physicians. Disc herniation, termed as intervertebral disc displacement, is amongst the most prevalent spinal diseases closely linked with IDD. Due to the same origins and similar pathophysiology, the ambiguity regarding the similarity and difference of IDD and intervertebral disc displacement thus remains. The aim of this study was to clarify the nomenclature of IDD and disc herniation in terms of molecular etiology, pathophysiology, nature history and clinical outcomes. Collectively, IDD is a type of multifaceted, progressive spinal disease with or without clinical symptoms as back pain, characterized by extracellular matrix and the integrity of NP and AF lost, fissures formation. Disc herniation (termed as intervertebral disc displacement) is a type of spinal disease based on IDD or not, with local pain and/or sciatica due to mechanical compression and autoimmune cascades upon the corresponding nerve roots. Clarifying the nomenclature of intervertebral disc degeneration and displacement has important implications both for investigators and for physicians.published_or_final_versio

Investigation of deformation behavior of cervical spine segment during the deformation of the intervertebral disc

In this paper the stress-strain state of the model cervical spine segment is regarded. The deformation behavior of the intervertebral disc during the deformation of the intervertebral disc is studied

The effects of running speed, form, and fatigue on intervertebral disc pressures at L5/S1: A developmental musculoskeletal and finite element modeling approach

The occurrence of low back pain in society is a widespread and costly problem, while running is an accessible and common form of physical exercise. The intervertebral disc is a commonly studied location of interest within the low back, however limited research has been performed attempting to assess the risks or benefits associated with running on the health of the intervertebral disc, with zero research which estimates in-vivo loading on the intervertebral disc during running. Meanwhile, the available literature is not in agreement on whether running poses more of a risk or a benefit to intervertebral disc health, with some research suggesting that running has the potential to positively affect the intervertebral disc, while additional research suggests that long distance running will increase the likelihood of injury among runners. Thus, it is of interest to determine in-vivo estimates of forces on the L5/S1 intervertebral disc in order to assess changes in pressure within the disc nucleus pulposus during running. As such, for this dissertation, three studies were completed. The first involved model development in order to estimate L5/S1 joint angles, forces, and moments, followed by further model development to estimate muscular forces crossing the L5/S1 joint and joint compressive forces, and concluding by utilizing a finite element model of the intervertebral disc to estimate joint pressure. Following model validation, two studies were completed using repeated measures study designs in order to compare changes in intervertebral disc pressure due to running at different velocities, using different footstrike patterns, and following fatigue. Validation of the models used when estimating in-vivo intervertebral disc pressures resulted in estimates for joint moments that were similar to those estimated during a previous research study. The shape of the curves estimating muscular forces were similar to muscular stimulation curves derived via electromyography (EMG), however due to limitations of the data collection process for both muscle modeling and EMG it was impossible to reach a strong agreement when comparing these data sources. Validation of the finite element model resulted in estimated disc compression leading to percent stature loss that was similar in error magnitude to some previously published research comparing in-vivo and simulated data. Comparisons of previously recorded in-vivo disc pressure for a single subject to estimations for the present study resulted in minimum pressures that were similar across the studies, with greater maximum pressure estimated using the current modeling approach. An increase in velocity resulted in an increase in the average and peak pressures on the intervertebral disc during running, while faster velocities resulted in reaching peak pressure later on in stance than slower velocities. Changing footstrike patterns did not cause any differences in average or peak intervertebral disc pressure, however running with a forefoot strike did cause runners to achieve peak intervertebral disc pressures earlier on during the stance phase than when running with a rearfoot strike pattern. During fatigued running, a moderate-large effect size was observed with higher pressures on the disc during the fatigued state which were not statistically significant (p\u3e0.05), and with no change in the percent stance needed to reach peak pressure. The models appear to perform adequately when utilized in a repeated measures study design, but are not able to accurately detect specific pressures within the intervertebral disc. The true meaning behind these results is unknown as higher pressures or loading rates during certain conditions may lead to increased risk of injury, or alternatively there might be little effect on injury risk as the higher pressure/loading may increase fluid flow into and out of the disc thus enhancing nutrient absorption. Further research needs to be performed in order to determine the risks associated with increases in pressure due to running at faster velocities, potential increases in the loading rate during forefoot strike running due to reaching peak pressure sooner than rearfoot strike running, and potential risks associated with increased intervertebral disc pressure during fatigued running

Experimental intervertebral disc degeneration models

Intervertebral disc degeneration is a major health problem of close concern to both young and old. The problem is also growing as the global population ages. Intervertebral disc degeneration is defined as progressive changes affecting the spine as a component of natural aging under the effect of multiple factors (such as smoking, obesity, and incorrect exercise). For a solution to be found, experimental disc degeneration must first be induced, the causes of the disease must be identified, and early diagnostic and therapeutic methods must then be developed. Methods of inducing intervertebral disc degeneration with high applicability in rats were identified from the previous literature. This review discusses four methods of disc degeneration induction. It also discusses how to detect degeneration formation and development times. As a result of the literature review, information about four different and reliable intervertebral disc degeneration methods is presented

Exhaustion of nucleus pulposus progenitor cells with ageing and degeneration of the intervertebral disc.

Despite the high prevalence of intervertebral disc disease, little is known about changes in intervertebral disc cells and their regenerative potential with ageing and intervertebral disc degeneration. Here we identify populations of progenitor cells that are Tie2 positive (Tie2+) and disialoganglioside 2 positive (GD2+), in the nucleus pulposus from mice and humans. These cells form spheroid colonies that express type II collagen and aggrecan. They are clonally multipotent and differentiated into mesenchymal lineages and induced reorganization of nucleus pulposus tissue when transplanted into non-obese diabetic/severe combined immunodeficient mice. The frequency of Tie2+ cells in tissues from patients decreases markedly with age and degeneration of the intervertebral disc, suggesting exhaustion of their capacity for regeneration. However, progenitor cells (Tie2+GD2+) can be induced from their precursor cells (Tie2+GD2-) under simple culture conditions. Moreover, angiopoietin-1, a ligand of Tie2, is crucial for the survival of nucleus pulposus cells. Our results offer insights for regenerative therapy and a new diagnostic standard